Methods may interact with object variables (attributes) and their associated data. But a method cannot directly interact with any object variable (attribute), only with those object variables (attributes) that are defined in the same class as the method (encapsulation). This protects the object variables' (attributes') data from being changed by "unauthorized" methods belonging to other classes.
All Methods of a particular class are able to directly access object variables (attributes) by using as their very first instruction the EXPOSE instruction followed by a blank delimited list of the object variable (attribute) names the method wishes to interact directly.